Outside broadcasting is the production of television or radio programmes (typically to cover news and sports events) from a mobile television studio. This mobile control room is known as an “Outside Broadcasting Van”, “OB Van”, “OB Bus”, “mobile unit”, “remote truck”, “live truck”, “live eye”, or “production truck”. The mobile OB Bus is positioned at, or near, a remote site of recording and signals from cameras and microphones on the remote site of recording come into the OB Bus for processing and transmission to a center for possibly final production and finally broadcasting. There is also a lot of verbal communication between the persons on the site and the persons in the OB Bus and communication of data besides the actual signals from cameras and microphones, such as meta data from the different equipment used to capture the signals on the site and control data used to control the cameras and microphones on the site from the OB Bus.
A crossbar switch is an assembly of individual switches between multiple inputs and multiple outputs. The switches are arranged in a matrix. If the crossbar switch has M inputs and N outputs, then a crossbar has a matrix with M×N cross-points or places where the “bars” cross. At each crosspoint is a switch; when closed, it connects one of M inputs to one of N outputs. A given crossbar is a single layer, non-blocking switch. Collections of crossbars can be used to implement multiple layer and/or blocking switches. A crossbar switching system is also called a co-ordinate switching system. One input can be connected to several outputs simultaneously, just as several inputs can be connected to one output simultaneously.
In this description it shall be understood that a communication matrix is a unit with the characteristics and logical function of a crossbar switch but which necessarily does not have to be a traditional hardware crossbar switch; it can be any switch with multiple inputs and outputs which can be controlled to connect one input to one or several outputs simultaneously and one or several inputs to one output simultaneously.
In a recording and production of media material there are several persons with different tasks involved, for example during a video production there are the persons at the actual site, such as camera men, audio technicians and reporters, and there are the persons in the OB Bus, such as video and audio technicians, mixers, producers, graphic designers, lightning artists and editors. These persons have to be able to communicate with each other, both on the site, within the OB Bus and also between the site and the OB Bus. For this it is known to use a communication matrix through which is it possible to enable the communication between any persons on the site of the event and in the OB Bus.
Some cameras for video production comprises the camera head and a camera control unit (CCU) where high speed real time communication must be maintained between the camera head and camera control unit during all time of capturing the video signal, both for communicating control signals to and from the camera head and for communicating the actual video signal. A multiplexed cable, usually a triaxial cable or hybrid fiber cable, is used for the communication between the camera head and the CCU. Each signal and function to control and manage the camera and the actual camera signal can be derived from the CCU and transported to the OB bus by means of any other type of signal transportation.
It is also known to provide remote video production where a distance can be found between the site for the event and the control room and where required communication is established between the site and control room by means of a data stream. An example of remote video production can be found in patent publication U.S. 2009/0290070 A1.